Plymouth's Conquest Is Something Out Of The Ordinary Road Test

December 21, 1985|by LEONARD KUCINSKI, The Morning Call

One of the hottest of the performance/sports cars for 1986 is the little known and less seen Plymouth Conquest with intercooled turbocharger. If you haven't seen this Conquest do more conquering, it probably is because there aren't enough of them around to fill a croquet court, much less command a company of commandos.

Here's a car you can drive and drive and drive and not worry about seeing duplications at every turn. In fact, you can search and search and search and not come up with a twin. This really wouldn't be that unusual if the Conquest were a low production car built by a small manufacturer. But since it does come from Chrysler/ Plymouth you should expect a little more in numbers. Or should you?

Well, not really. The Conquest is a manufactured by Mitsubishi Motors of Japan and is at the lower end of the import quota. It seems there really aren't enough of them to get anyone excited at Chrysler. That is, excited enough to advertise them a little. Also, the Conquest is really in competition with Chrysler's domestically-built performance cars - most noteably the Laser - so there is probably some lack of interest at that end. But if you want to talk about a real sleeper, the Conquest is it.

But then, any time you have 170 horsepower in a car weighing about 2,600 pounds you should expect a little out of the ordinary in performance.

The test car - supplied by Rothrock Chrysler/Plymouth, 15th Street and Route 22 - was all black with a mean appearance and looked like something Burt Reynolds raced against in the Cannonball. It was mistaken for a Mazda RX7, Nissan 300Z, Toyota Supra and Porsche (911, 928 and 911, take your choice). In fact, no one identified it for what it was. This really wasn't a surprise. It wasn't even a surprise that no one knew what an intercooled turbocharger was. I'm sure all you readers do, but for the record, we'll review it.

To have an intercooled turbocharger, first, obviously, a turbocharger is needed. Until several years ago, turbocharging was something that was done to engines of racing cars. This pump-type device that is run off exhaust gases became popular on passenger cars as a means of increasing horsepower on small engines while still retaining some fuel economy. By compressing the fuel/air mixture, it produced a bigger charge in the combustion chamber and subsequently an increase in performance.

The intercooler - used on a very limited number of cars today - takes this process one step further by removing much of the turbo-induced heat from the engine's intake air, increasing the density of the fuel/air mix and optimizing combustion. Now we are going to run over this just a little slower. Even under the best of conditions, the heat generated during rapid turbo compression of air partially counteracts the turbocharger's function of maximizing air density because heat causes the air toexpand, reducing its density. If the turbocharger increases pressure of the air used in the engine combustion process by 100 percent, for example, the density of the air is increased by only about 60 percent because of the heat expansion phenomena.

By sending turbo air from the turbocharger through the intercooler, the turbocharged air going to the engine is cooled and its density substantially increased. This cooler air greatly increases combustion efficiency and optimizes engine performance. It also reduces the tendency of "over hot" turbo air to cause engine knock under certain driving conditions. For all it does, the Conquest's intercooler is rather compact. It measures 8 by 16 by 2.5 inches and is located just beneath the front air dam.

But really what does this mean in practical terms? To answer this, first we'll take the basic engine - Mitsubishi's 2.6 liter (156 cubic inches) overhead cam, four-cylinder MCA-Jet, Silent Shaft engine. In a non-turbo version (available on domestic Chrysler products but not the Conquest) it is rated at 104 horsepower at 4,800 rpm and 142 foot pounds torque at 2,800 rpm. With a turbocharger (the standard engine in the Conquest), power is increased to 145 horsepower at 5,000 rpm and 185 foot pounds torque at 2,500 rpm. Not bad at all. But with the intercooler, the engine is rated at 170 horsepower at 5,000 rpm and 220 foot pounds torque at 2,500 rpm.

Without belaboring the issue too much, let's just say that performance is impressive. The test car was not broken in so I did not push it to its fullest. But even then I had more than enough power for all Lehigh Valley driving conditions, and then some. The engine together with the five-speed manual transmission (standard, a four-speed automatic is available) produced decent fuel mileage - 16 miles per gallon city and 24 mpg over the highway. Becauseof the demands of the turbocharger, unleaded premium is required.